Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
dinh dai » dinh dat, dinh dao, dinh tai
sinh dai » sinh thai, si dai, sinh vat
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
y sang » _ sang, duy sang
ma hoi » mai hoi, xa hoi, me hoi
cua te » cua tu
ve am » va am

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y sang ((ma hoi) OR (ma hoa)). hieu ve am thuc dan ((dinh dai) or (sinh dai)) cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y sang ((ma hoi) OR (ma hoa)). hieu ve am thuc dan ((dinh dai) OR (sinh dai)) cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y sang ((ma hoi) OR (ma hoa)). hieu ve am thuc dan ((dinh dai) or (sinh dai)) cua te".
• Adding a wildcard symbol may retrieve word variants: su sach y sang ((ma hoi) OR (ma hoa)). hieu ve am thuc dan ((dinh dai) or (sinh dai)) cua te*.